Here are a few from the archives but I'd love to hear some of your favorite quotes specifying manners and/or gracious living:
Manners are a sensitive awareness of the feelings of others. If you have that awareness, you have good manners, no matter what fork you use. Emily Post (1872-1960)
Good manners will open doors that the best education cannot.
Clarence Thomas (1948 - )
Rudeness is the weak man's imitation of strength.
Eric Hoffer (1902 - 1983)
It is wise to apply the oil of refined politeness to the mechanisms of friendship. Colette (1873 - 1954)
I look forward to your responses.